! radiation_cloudless_sw.F90 - Shortwave homogeneous cloudless solver ! ! (C) Copyright 2019- ECMWF. ! ! This software is licensed under the terms of the Apache Licence Version 2.0 ! which can be obtained at http://www.apache.org/licenses/LICENSE-2.0. ! ! In applying this licence, ECMWF does not waive the privileges and immunities ! granted to it by virtue of its status as an intergovernmental organisation ! nor does it submit to any jurisdiction. ! ! Author: Robin Hogan ! Email: r.j.hogan@ecmwf.int ! module radiation_cloudless_sw public :: solver_cloudless_sw contains ! Provides elemental function "delta_eddington" #include "radiation_delta_eddington.h" !--------------------------------------------------------------------- ! Shortwave homogeneous solver containing no clouds subroutine solver_cloudless_sw(nlev,istartcol,iendcol, & & config, single_level, & & od, ssa, g, albedo_direct, albedo_diffuse, incoming_sw, & & flux) use parkind1, only : jprb use yomhook, only : lhook, dr_hook, jphook use radiation_config, only : config_type use radiation_single_level, only : single_level_type use radiation_flux, only : flux_type, indexed_sum_profile, & & add_indexed_sum_profile use radiation_two_stream, only : calc_two_stream_gammas_sw, & & calc_reflectance_transmittance_sw use radiation_constants, only : Pi, GasConstantDryAir, & & AccelDueToGravity use radiation_adding_ica_sw, only : adding_ica_sw implicit none ! Inputs integer, intent(in) :: nlev ! number of model levels integer, intent(in) :: istartcol, iendcol ! range of columns to process type(config_type), intent(in) :: config type(single_level_type), intent(in) :: single_level ! Gas and aerosol optical depth, single-scattering albedo and ! asymmetry factor at each shortwave g-point real(jprb), intent(in), dimension(config%n_g_sw, nlev, istartcol:iendcol) :: & & od, ssa, g ! Direct and diffuse surface albedos, and the incoming shortwave ! flux into a plane perpendicular to the incoming radiation at ! top-of-atmosphere in each of the shortwave g points real(jprb), intent(in), dimension(config%n_g_sw,istartcol:iendcol) :: & & albedo_direct, albedo_diffuse, incoming_sw ! Output type(flux_type), intent(inout):: flux ! Local variables ! Cosine of solar zenith angle real(jprb) :: cos_sza ! Diffuse reflectance and transmittance for each layer real(jprb), dimension(config%n_g_sw, nlev) :: reflectance, transmittance ! Fraction of direct beam scattered by a layer into the upwelling ! or downwelling diffuse streams real(jprb), dimension(config%n_g_sw, nlev) :: ref_dir, trans_dir_diff ! Transmittance for the direct beam in clear and all skies real(jprb), dimension(config%n_g_sw, nlev) :: trans_dir_dir ! Fluxes per g point real(jprb), dimension(config%n_g_sw, nlev+1) :: flux_up, flux_dn_diffuse, flux_dn_direct ! Combined optical depth, single scattering albedo and asymmetry ! factor real(jprb), dimension(config%n_g_sw) :: od_total, ssa_total, g_total ! Two-stream coefficients real(jprb), dimension(config%n_g_sw) :: gamma1, gamma2, gamma3 ! Number of g points integer :: ng ! Loop indices for level and column integer :: jlev, jcol real(jphook) :: hook_handle if (lhook) call dr_hook('radiation_cloudless_sw:solver_cloudless_sw',0,hook_handle) ng = config%n_g_sw ! Loop through columns do jcol = istartcol,iendcol ! Only perform calculation if sun above the horizon if (single_level%cos_sza(jcol) > 0.0_jprb) then cos_sza = single_level%cos_sza(jcol) ! The following is the same as the clear-sky part of ! solver_homogeneous_sw if (.not. config%do_sw_delta_scaling_with_gases) then ! Delta-Eddington scaling has already been performed to the ! aerosol part of od, ssa and g do jlev = 1,nlev call calc_two_stream_gammas_sw(ng, cos_sza, & & ssa(:,jlev,jcol), g(:,jlev,jcol), & & gamma1, gamma2, gamma3) call calc_reflectance_transmittance_sw(ng, & & cos_sza, & & od(:,jlev,jcol), ssa(:,jlev,jcol), & & gamma1, gamma2, gamma3, & & reflectance(:,jlev), transmittance(:,jlev), & & ref_dir(:,jlev), trans_dir_diff(:,jlev), & & trans_dir_dir(:,jlev) ) end do else ! Apply delta-Eddington scaling to the aerosol-gas mixture do jlev = 1,nlev od_total = od(:,jlev,jcol) ssa_total = ssa(:,jlev,jcol) g_total = g(:,jlev,jcol) call delta_eddington(od_total, ssa_total, g_total) call calc_two_stream_gammas_sw(ng, & & cos_sza, ssa_total, g_total, & & gamma1, gamma2, gamma3) call calc_reflectance_transmittance_sw(ng, & & cos_sza, od_total, ssa_total, & & gamma1, gamma2, gamma3, & & reflectance(:,jlev), transmittance(:,jlev), & & ref_dir(:,jlev), trans_dir_diff(:,jlev), & & trans_dir_dir(:,jlev) ) end do end if ! Use adding method to compute fluxes call adding_ica_sw(ng, nlev, incoming_sw(:,jcol), & & albedo_diffuse(:,jcol), albedo_direct(:,jcol), & & spread(cos_sza,1,ng), reflectance, transmittance, ref_dir, trans_dir_diff, & & trans_dir_dir, flux_up, flux_dn_diffuse, flux_dn_direct) ! Sum over g-points to compute and save clear-sky broadband ! fluxes flux%sw_up(jcol,:) = sum(flux_up,1) if (allocated(flux%sw_dn_direct)) then flux%sw_dn_direct(jcol,:) = sum(flux_dn_direct,1) flux%sw_dn(jcol,:) = sum(flux_dn_diffuse,1) & & + flux%sw_dn_direct(jcol,:) else flux%sw_dn(jcol,:) = sum(flux_dn_diffuse,1) + sum(flux_dn_direct,1) end if ! Store spectral downwelling fluxes at surface flux%sw_dn_diffuse_surf_g(:,jcol) = flux_dn_diffuse(:,nlev+1) flux%sw_dn_direct_surf_g(:,jcol) = flux_dn_direct(:,nlev+1) ! Save the spectral fluxes if required if (config%do_save_spectral_flux) then call indexed_sum_profile(flux_up, config%i_spec_from_reordered_g_sw, & & flux%sw_up_band(:,jcol,:)) call indexed_sum_profile(flux_dn_direct, config%i_spec_from_reordered_g_sw, & & flux%sw_dn_band(:,jcol,:)) if (allocated(flux%sw_dn_direct_band)) then flux%sw_dn_direct_band(:,jcol,:) & & = flux%sw_dn_band(:,jcol,:) end if call add_indexed_sum_profile(flux_dn_diffuse, & & config%i_spec_from_reordered_g_sw, & & flux%sw_dn_band(:,jcol,:)) end if if (config%do_clear) then ! Clear-sky calculations are equal to all-sky for this ! solver: copy fluxes over flux%sw_up_clear(jcol,:) = flux%sw_up(jcol,:) flux%sw_dn_clear(jcol,:) = flux%sw_dn(jcol,:) if (allocated(flux%sw_dn_direct_clear)) then flux%sw_dn_direct_clear(jcol,:) = flux%sw_dn_direct(jcol,:) end if flux%sw_dn_diffuse_surf_clear_g(:,jcol) = flux%sw_dn_diffuse_surf_g(:,jcol) flux%sw_dn_direct_surf_clear_g(:,jcol) = flux%sw_dn_direct_surf_g(:,jcol) if (config%do_save_spectral_flux) then flux%sw_up_clear_band(:,jcol,:) = flux%sw_up_band(:,jcol,:) flux%sw_dn_clear_band(:,jcol,:) = flux%sw_dn_band(:,jcol,:) if (allocated(flux%sw_dn_direct_clear_band)) then flux%sw_dn_direct_clear_band(:,jcol,:) = flux%sw_dn_direct_band(:,jcol,:) end if end if end if ! do_clear else ! Set fluxes to zero if sun is below the horizon flux%sw_up(jcol,:) = 0.0_jprb flux%sw_dn(jcol,:) = 0.0_jprb if (allocated(flux%sw_dn_direct)) then flux%sw_dn_direct(jcol,:) = 0.0_jprb end if flux%sw_dn_diffuse_surf_g(:,jcol) = 0.0_jprb flux%sw_dn_direct_surf_g(:,jcol) = 0.0_jprb if (config%do_clear) then flux%sw_up_clear(jcol,:) = 0.0_jprb flux%sw_dn_clear(jcol,:) = 0.0_jprb if (allocated(flux%sw_dn_direct_clear)) then flux%sw_dn_direct_clear(jcol,:) = 0.0_jprb end if flux%sw_dn_diffuse_surf_clear_g(:,jcol) = 0.0_jprb flux%sw_dn_direct_surf_clear_g(:,jcol) = 0.0_jprb end if if (config%do_save_spectral_flux) then flux%sw_dn_band(:,jcol,:) = 0.0_jprb flux%sw_up_band(:,jcol,:) = 0.0_jprb if (allocated(flux%sw_dn_direct_band)) then flux%sw_dn_direct_band(:,jcol,:) = 0.0_jprb end if if (config%do_clear) then flux%sw_dn_clear_band(:,jcol,:) = 0.0_jprb flux%sw_up_clear_band(:,jcol,:) = 0.0_jprb if (allocated(flux%sw_dn_direct_clear_band)) then flux%sw_dn_direct_clear_band(:,jcol,:) = 0.0_jprb end if end if end if end if ! sun above horizon end do if (lhook) call dr_hook('radiation_cloudless_sw:solver_cloudless_sw',1,hook_handle) end subroutine solver_cloudless_sw end module radiation_cloudless_sw